docs: def root_sections(h):
      """
      Returns a list of all sections that have no parent.
      """
      roots = []
      for section in h.allsec():
          sref = h.SectionRef(sec=section)
          # has_parent returns a float... cast to bool
          if sref.has_parent() < 0.9:
              roots.append(section)
      return roots